[Ultrastructural observations of cat cortical neurons, labeled by the retrograde method, 8 days after injection of horseradish peroxidase].

The ultrastructural characteristics of cat's cortical neurons labeled by retrograde transport of horseradish peroxidase (HRP) have been studied; the cats were sacrificed 8 days after the injection of the enzyme. The aim of this study was principally to observe the evolution of neurons in which HRP had been assumed in diffused as well as in granular form - "diffuse-granular HRP neurons" -, or only in diffused form - "Golgi-like neurons" -. The results obtained show the scanty presence of diffuse-granular HRP cells and the contemporary presence of two populations of Golgi-like cells. In this study is underlined the difference between the observations conducted on specimens from cats sacrificed 48 hours or 8 days after the injection of the HRP.